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    <header>顶部广告</header>
    <main class="middle border">
      <h1 contenteditable>文章标题</h1>
      <section>
        <h2>第一章</h2>
        <p>
          这是一段话这是一段话这是一段话这是一段话这是一段话这是一段话这是一段话这是一段话这是一段话这是一段话
        </p>
        <section>
          <h3>1.1节</h3>
          <p>一段话</p>
        </section>
        <section>
          <h3>1.2节</h3>
          <p>一段话</p>
        </section>
      </section>
    </main>
    <aside>
      参考资料 1 2 3 4 5
    </aside>
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